Thread: Help with Proof
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Old 04-05-2008, 04:37 PM
Ron_Mexico Ron_Mexico is offline
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Help with Proof

Any math whizzes out there? Could you help me prove that:

Cos (pi/5) = (1 + square root of 5)/4

Note that the second expression is the quantity of one plus the square root of five divided by four (hence the parenthesis).

Much appreciated.
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